feat: Convert to a multi-host flake

hosts/crossbox/ollama.nix

@@ -0,0 +1,24 @@
+{ config, pkgs, lib, ... }:
+
+{
+  services.ollama = {
+    enable = true;
+    host = "0.0.0.0";
+    port = 11434;
+  };
+  
+  # Open firewall port for Ollama
+  networking.firewall.allowedTCPPorts = [ 11434 ];
+  
+  # Install ollama-rocm package
+  environment.systemPackages = with pkgs; [
+    ollama-rocm
+  ];
+  
+  # Add CA certificate for Ollama
+  # Note: Path must be accessible at runtime, not build time
+  # You can copy the cert to /etc/nixos/ and reference it, or use a string path
+  # security.pki.certificateFiles = [
+  #   "/home/brimlock/ollama-ca.crt"
+  # ];
+}